Wireless solar water heater controller ensures hot water every time

water-heater-controller

[Peter Sobey] had a solar hot water heater installed in his home, which worked great until he relocated his kitchen to a neighboring room. Now a good bit further from the tank, the hot water reaching his sink was tepid at best due to the increased distance and temperature limiting mixer valve in the new heater.

He installed a salvaged solar panel and water tank solely for use in his kitchen, but as the panel was located above the tank, he had to find a way to actively monitor and control the water temperature. His pump and valve system was originally driven with an off the shelf PICAXE-based controller, but he eventually got the urge to add a wireless display and control panel to the mix.

A pair of Arduino Nanos run the show now, one of which resides in the pump controller box, while the other is used in the temperature display box in his kitchen. He uses a set of Bluetooth modules to link the Arduinos together, relaying temperature data and allowing him to send the pump controller manual commands if needed.

He says the system works a treat, and he’s much happier with his homebrew controller than the one he used originally.

Human-shaped planes troll NYC

It looks like a genetic leap has unleashed the age of mutants, but this is really just a few guys trolling New York City with some custom RC aircrafts. The video after the break shows the fliers up close. They’re pretty much full size, we’d guess 5’10” from head to heel. The outstretched arms and body act as wings, while the legs act as ailerons and rudders. But from afar (or even a medium distance) it’s quite difficult to make out the flat surfaces… they look like office workers loosed from their cubicles. Unfortunately we don’t have more than a flight demo to share with you. If you know where to find build info (or any extra details at all actually) don’t forget to send in a tip We wonder if these are the same guy who made the flying hero we posted back in July?

There’s another nugget of delight right at the beginning of the video. A sweet octocopter which looks much like this one was used to capture the aerial footage.

[Read more…]

Tethering a Kindle for free 3G

[Excelangue] just posted a guide to using the free 3G connection in your Amazon Kindle to browse the Internet on your computer.

The hack requires a Kindle Keyboard 3G and the free worldwide Internet access that comes along with the purchase price. After jailbreaking the Kindle and applying a USB network hack, [Excelangue] managed to connect his laptop to the Internet through his computer. The process of tethering the Kindle’s 3G is remarkably easy, but we expect a one-click solution will pop up on the web sometime this week.

Of course we have to note here that tethering a Kindle is against the Amazon terms & conditions, and the data going through your Kindle is tied to a unique ID. If you do this, Amazon knows who you are and is more than likely willing to brick your device. [Excelangue] is looking into tethering to the Kindle over WiFi so Android and iOS devices can get in on the action, but he’s still in the process of experimenting with his build.

Get neck-deep into ZigBee

Here’s a bulky tutorial that will round-out your understanding of ZigBee wireless communications (translated). The protocol is great for hobby electronics projects because it uses low-power short range wireless devices to build a mesh network. The guide covers both hardware and software, but also takes the time to explain what that hardware is doing in the background.

As you can see, several different renditions of an XBee module are used as examples. They pretty much all rely on a series of SparkFun breakout boards that each serve different purposes. Once you’ve acquired these modules, there’s a fair number of choices needed to configure them to play nicely with each other. We read most of the tutorial (we’ll save the rest for later enjoyment) and had no problem following along even without owning the hardware or being able to use the interface as we learned.

Whenever we cover XBee modules we always like to mention that it’s quite easy to use these for remote sensors with no additional microcontroller needed.

Quadcopter build ready for first flight

[Abhimanyu Kumar] has been hard at work building and posting about his quadcopter. So far he’s published ten installments for this build, letting us relive the adventure vicariously. But it’s number 11 that we’re really excited about as he plans to share the first free-flight footage in that one.

The bug was planted in his brain after hearing that a quadcopter was used to shoot some of the footage in Spiderman 2. He wanted one to call his very own but the cost of a ready-made unit was out of his league. So he decided to build one instead. The first version uses aluminum bracket for the cross making up the motor mounts. He added LEDs to liven things up and even made a demo video of the thing tied to a table (no IMU yet so free flight would be fatal). After this stepping stone he decided to go with a Wii Motion Plus and Wii Nunchuck as the positioning feedback sensors. There is also a body redesign with helps lighten the load.

It’s a fun project, and we can’t wait to see where he goes from here!